Passengers, who had set off from London City Airport, only found out about the mishap when the pilot said the plane was coming in to land in Edinburgh, which is around 800 kilometres from Düsseldorf, in North Rhine-Westphalia.
After the crew realized the mistake, the plane was refuelled and flown to Düsseldorf, landing in Germany with a delay of more than three and a half hours.
BA declined to say how many passengers were affected by the mistake, reported the BBC.
The airline giant also said the pilot wasn't lost at any point, but because the paperwork said Edinburgh, the flight simply took that route.
“We are working with WDL Aviation, who operated this flight on behalf of British Airways, to establish why the incorrect flight plan was filed,” a spokesman said.
Twitter user Son Tran, who said he was on the plane, said: “While an interesting concept, I don't think anyone on board has signed up for this mystery travel lottery”.
@British_Airways can you please explain how can my morning flight taking off from LCY to Dusseldorf land in Edinburgh ?? While an interesting concept, I don't think anyone on board has signed up for this mystery travel lottery… #BA3271 #frequenttravel #britishairways
— Son Tran (@sontrantuan) March 25, 2019
Another passenger, Sophie Cooke, told the BBC that the wait in Edinburgh “became very frustrating”.
“The toilets were blocked and they ran out of snacks. It was also really stuffy,” Cooke said.